ENGINE QUIT WHILE DRIVING/CRANKS BU

Hello, my son has a 96 Mits. Eclipse, he just had a new clutch installed a week ago. He said he was driving appro 60mph and all the dash lights illuminated and the engine quit, he tried to crank it over, it does crank but wont turn over. He was able to get 4 codes off of it. 11, 12, 54 & 55. I work at a bodyshop & svc center where the clutch was installed and the assistant did do something with the LT FT wheel (some welding was involved) but I just dont know! His biggest fear is the timing chain, but he said it seems to be intact, and the plugs arent bent. Do you have any advise for us?